title: Risk of Pneumocystis jiroveci pneumonia in patients long after renal transplantation.
abstract: BACKGROUND
  Pneumocystis jiroveci pneumonia (PCP) is an important cause of morbidity and mortality in renal transplant recipients (RTRs). Chemoprophylaxis with trimethoprim/sulphamethoxazole is recommended during the early post-transplantation period, but the optimal duration has not been determined and a main drawback of chemoprophylaxis is the development of resistance of the commensal faecal flora. A cluster outbreak of PCP occurred in our outpatient Renal Transplant Unit. We aimed to investigate risk factors for PCP in RTRs to determine who should receive long-term chemoprophylaxis.
  
  
  METHODS
  In a case-control study, we investigated common demographic variables and immunological parameters. Nine PCP cases diagnosed between August 2006 and April 2007 were matched with 18 control patients, who did not develop PCP, received their transplant in the same time-period and had a similar follow-up period with a comparable immunosuppressive drug regimen.
  
  
  RESULTS
  The median time from transplantation to PCP was 19 months. We observed no significant differences in gender, age, donor type or number of rejections. In PCP cases, the median lymphocyte count just before PCP diagnosis was 0.49 (0.26-0.68), which was significantly reduced compared to the control patients after a similar follow-up period (median 1.36, 0.59-3.04, P = 0.002). This lymphocytopaenia was chronic and existed in most patients already for many months. CD4(+) T-cell counts were also significantly reduced in the PCP cases. We found no difference in the Th1, Th2 and Th17 subsets between PCP cases and control patients.
  
  
  CONCLUSIONS
  Long-term prophylactic therapy for PCP may be indicated for RTR with persistent severe lymphocytopaenia.
authors.affiliation: Renal Transplant Unit, Department of Nephrology, Division of Internal Medicine, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands. g.h.struijk@amc.uva.nl
authors.forename: Geertrude H
authors.initials: GH
authors.lastname: Struijk
authors.forename: Anton F
authors.initials: AF
authors.lastname: Gijsen
authors.forename: Si La
authors.initials: SL
authors.lastname: Yong
authors.forename: Aeilko H
authors.initials: AH
authors.lastname: Zwinderman
authors.forename: Suzanne E
authors.initials: SE
authors.lastname: Geerlings
authors.forename: Kamilla D
authors.initials: KD
authors.lastname: Lettinga
authors.forename: Karlijn A M I
authors.initials: KA
authors.lastname: van Donselaar-van der Pant
authors.forename: Ineke J M
authors.initials: IJ
authors.lastname: ten Berge
authors.forename: Frederike J
authors.initials: FJ
authors.lastname: Bemelman
mesh_terms: D000328:Adult; D000368:Aged; D000890:Anti-Infective Agents / Q000627:therapeutic use; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000628:therapy; D007677:Kidney Function Tests; D016030:Kidney Transplantation / Q000009:adverse effects*; D018655:Lymphocyte Count; D008231:Lymphopenia / Q000175:diagnosis / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D016720:Pneumocystis Infections / Q000209:etiology*; D045363:Pneumocystis carinii / Q000302:isolation & purification*; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000627:therapeutic use
chemical_list: D000890:Anti-Infective Agents; D007166:Immunosuppressive Agents; D015662:Trimethoprim, Sulfamethoxazole Drug Combination